Ive been running only Jet A in my P120 with the standard oil mix. After going to superman, I noticed everyone using Kerosene. Is it simply because Kerosene is easier to buy than Jet A? Or is there another reason?

Thanks,
Mike

Yep

Is there any real difference between the two?

jet A usually smells worse. Other than that I couldn't tell the difference.[8D]

i have used both, and I have seen a big difference, if you can, stay with jet A. i started out this year with jet A, i ran out of jet A and the airport was closed , so i went to the local gas station and got kerosene. the only difference i have seen ,was on the start ups, i have not seen any difference in the air. the starts with jet A seem to be smooth, when i run kerosene, it seems to kind of spit and kind of cough a little on the starts, NOT smooth, but again, with jet A very smooth starts.

mark

Over the last 4 years (700+ flights) I have used both Jet A and kerosene and have found no difference in engine teperatures or pump voltages during starts or while running/accelerating. Although Jet A for me is a lot cheaper I have been sticking with kero for my P-120's the last season or so because it does not smell near as bad as the Jet A, and the smell does not linger for weeks like Jet A does if spilled....ron

From talking to John Redman from Jetcat (hopefully he'll chime and in and give a more technical reason) Jet A is much more lubracative than kerosene is. So if you forget to add oil to your fuel can there will be much less damage with Jet A than with kerosene.

That being said....I still run kerosene. It's just a convenience thing. I can get kero in 5 gal cans from my local hardware store.

Bob

When you run varying grades of Jet Fuel say JP4 or Jet A the overhaul time of the turbine changes as well as the min temp you can operate at. That doesn't effect us but I am sure the Jet A has better lubricating then straight kerosene but since we mix oil with our does that even matter.

I have even seen a turbine run on Jack Daniels and funny thing is it smelled better.

The only question I am unsure about is prist does anyone use it in there Jet Fuel it prevents bacteria or fungus?

Ian

It does if you forgot which container you put the oil into!

A Qantas (I'm assuming he was a tubine tech) guy at my field recently told me that A-1 has an antifreeze in it, and that's the only difference. Other jet fuels have stuff in them that make them different. In Sydney most people use A-1 because there aren't any gas stations that have kero on pump anymore, and because the A-1 will be fresh, whereas if you find a place with kero on pump it could be old and cruddy. To add another question while we're talking fuels, I know most/all turbine guys use a small hopper tank to remove air bubbles. Has anyone toyed with the idea of adding an anti-foaming agent to the fuel? I know the motor racing fuels and oils have it mixed in them - perhaps it may help a bit?

I HAVE HEARD OF GUYS GOING TO HOME DEPOT. AND DUYING FUEL. THEY WERE TALKING ABOUT PARAFIN? I THINK THAT IS SPELLED CORRECT. ANY ONE USEING THAT?

SORRY THE SPELL CHECKER DID NOT WORK!!

Kerosene Type Jet Fuel also known as Jet A consist essentially of the heavier hydrocarbon fractions and are more dense than the wide cut gasoline type fuel ( Jet B ). There is NO specific gravity or vapor pressure difference between Kerosene and Jet A. There is however, most often the addition of PRIST ( PFA 55MB covered by MIL-I-27686D ) main ingredient ethylene glycol monomethyl ether to Jet A. Prist is added to prevent icing and bacterial contamination ONLY. The recommended concentration of Prist in fuel is 0.06 - 0.15 percent by volume.

The above information as noted in Aircraft Powerplants 6th edition ( Kroes,Wild, Bent, McKinley )

Dean
www.helijet.ca

I did some test on a test stand over 7 years ago with Jet A and Kero with a Pegasus..
And the result were exactly the same.. Both ran the same temp and powered up
exactly the same..

One thing I like about Jet A is my 55 gal drum does not have one bit of growth
after many many years.. I don't know if Kero would have stopped any growth
but I have first hand experience with junk growing in diesel tanks.

Eddie Weeks

Jet A is refined slightyly different by including another step. Besides the Anti-Freeze additiive, more of the sulpher is removed from Jet A than Kerosene which in turn allows full sized jets to make less of the black smoke during combustion (remember the old movies of B-52's, 707's etc). Other than that there is no difference.

While we are on this fuel topic...how about oil. Ive used the Aeroshell. However, yesterday, I couldnt find any but I could find BP turbine oil. Any difference?

Mike

Dean

Regarding Prist very few times has anyone in the modeling community brought up this additive. In North America it is optional to have Jet A with or without. However I found out today that Pratt & Whitney advoacates the use of Prist in there turbines.

One last thing I have seen fuel tanks that used Prist and they are pristine. But in talking with several Prist users today I found off that it no longer guards against bacteria growth.

The above comments were made with full size axial flow turbines and full size aircraft not sure where the model community would fit in this Prist issue since we typically drain the tanks except the UAT or hopper.

Ian

All Prist is, is a ani-icing aditvie (sp).

heres another question for Jet A..is it better to break in your turbine on one or the other? I prefure to use JetA just because I work at a airport and can get it cheap. so is it really better then kero.?

Mike, the regarding turbine oil, I have use BP 2380, Exxon 2380, Aero-Shell 500 in my Simjet and the 600 are all good to use in the turbines, Simjet recomends Exxon 2380, Aero-Shell 500 or 600, so its all good.

I prefer KA-1 easy to get at the home depot or other hardwere store, it comes in 5 gls. containers ( the black can )I keep 5 gls. in my can and 5 gls. as reserve, its supper clean too.


CARS II

I have ran both and also notice no difference. I do use Jet-A because it is half the cost of K-1 and I can write the cost off because it is an aircraft fuel.

Jet-A does smell terrible though!! I spilled some in the bed of my truck and I could smell it for weeks even after pressure washing the truck off.

In the instructions for my Wren turbine it mentions first & second choice for both fuel & oil.
'Fuel - The engine is designed to run on paraffin (kerosene) such as is available at B&Q and similar DIY stores or at filling stations from the pump. Alternatively Jet A or Jet A1 kerosine is suitable where available.' - John.

I researched this several months ago after having an algae problem with kerosene I bought at a local hardware store. Prist is used in aircraft fuel as an anti-icing additive and to prevent bacterial or algae growth. For some reason the manufacturer stopped advertising it as anti-bacterial a few years ago. It's still the same stuff and still is effective at preventing bacteria growth. Now they just market it as an anti icing compound, I suspect that there was some legal reason for the change.

Kerosene is more readily available and cheaper than Jet A, at least around here, plus I don't like the smell of Jet A. Because of my past algae problem I bought a product at a local marine supply store that is used by boaters to prevent algae growth in diesel fuel. According to the bottle it is also effective in kerosene and aviation fuel. The 12 oz. bottle I bought is enough to treat 800 gallons. Looks like I have enough to last the rest of my life.

Joe

Joe, what are you paying for kero up there? Pump or bottled?
Do you remember the name of that fuel treatment?

JOe Kelley !~)

I use both Kerosene and JetA.
I'm lucky enough to have a friend in the helicopter business and I have unlimited JetA resources.

My local hardware store sells Kerosene cheap from the pump, but it's red dye. I never tried it, not sure if it will do any damage.